Burgess Shale fossils illustrate the origin of the mandibulate body plan

@article{Aria2017BurgessSF,
  title={Burgess Shale fossils illustrate the origin of the mandibulate body plan},
  author={C{\'e}dric Aria and Jean‐Bernard Caron},
  journal={Nature},
  year={2017},
  volume={545},
  pages={89-92}
}
Retracing the evolutionary history of arthropods has been one of the greatest challenges in biology. During the past decade, phylogenetic analyses of morphological and molecular data have coalesced towards the conclusion that Mandibulata, the most diverse and abundant group of animals, is a distinct clade from Chelicerata, in that its members possess post-oral head appendages specialized for food processing, notably the mandible. The origin of the mandibulate body plan, however, which… 

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